#include<stdio.h>
int main()
{
    int x;
    scanf("%d",&x);
    if(3000/x>=15)
    printf("15");
    else if(3000%x==0)
    printf("%d",3000/x);
    else if(3000%x!=0)
    printf("%d",3000/x+1);
    return 0;
}